Manganese oxide composite electrodes for lithium batteries

Abstract

An activated electrode for a non-aqueous electrochemical cell is disclosed with a precursor thereof a lithium metal oxide with the formula xLi 2 MnO 3 .(1−x)LiMn 2−y M y O 4 for 0.5<x<1.0 such that the spinel component constitutes less than 50 mole % of the precursor electrode and 0≦y<1 in which the Li 2 MnO 3 and LiMn 2-y M y O 4 components have layered and spinel-type structures, respectively, and in which M is one or more metal cations. The electrode is activated by removing lithia, or lithium and lithia, from the precursor. A cell and battery are also disclosed incorporating the disclosed positive electrode.

1. An activated electrode for a non-aqueous electrochemical cell, having as a precursor thereof a lithium metal oxide with the formula xLi 2 MnO 3 •(1−x)LiMn 2−y M y O 4  for 0.5<x<1.0 such that the spinel component constitutes less than 50 mole % of the precursor electrode and 0≦y<1 in which the Li 2 MnO 3  and LiMn 2−y M y O 4  components have layered and spinel-type structures, respectively, and in which M is one or more metal cations, said activated electrode being activated by removing lithia, or lithium and lithia, from said precursor. 
     
     
       2. The activated electrode according to  claim 1 , in which the spine) component is an end-of-charge indicator and/or an end-of-discharge indicator. 
     
     
       3. The activated electrode according to  claim 1 , in which M is one or more monovalent, divalent, trivalent or tetravalent cations. 
     
     
       4. The activated electrode according to  claim 3 , in which M is one or more Li + , Mg 2+ , Ni 2+ , Ni 3+ , Co 2+ , Co 3+ , Al 3+ , Ti 4+  and Zr 4+  ions. 
     
     
       5. The activated electrode according to  claim 1 , in which the manganese ions, or the lithium and manganese ions of the Li 2 MnO 3  component are partially substituted by M cations. 
     
     
       6. The activated electrode according to  claim 1 , in which the components are partially reduced to provide mixed Mn 4+/3+  valence in the precursor electrode. 
     
     
       7. The activated electrode of  claim 1  and further including a negative electrode, and an electrolyte, said activated electrode being activated by removing lithia, or lithium and lithia, from said precursor, thereby forming an electrochemical cell. 
     
     
       8. A plurality of electrochemical cells of  claim 7  arranged in parallel and/or in series to form a battery.